A laser system comprises a plurality of lasers and a plurality of laser processing units which are each connected to the respective laser by means of a laser light cable and a data line which is parallel therewith. Each laser processing unit has a safety circuit which verifies the state (open or closed) of an operating cabin of the laser processing unit and in the event of an open operating cabin transmits a stop signal to the laser control of the associated laser.
In laser systems having a plurality of lasers and laser processing units the electrical safety circuits are intended to be monitored by a central safety control such as, for example, a programmable logic safety control (safety PLC) to which all the lasers and laser processing units are connected by means of a bus (safety bus). In order to be connected to the safety bus, a corresponding bus interface is provided on each laser.
When the laser system is constructed, not only the laser light cables have to be connected to the lasers but also the bus interfaces of the lasers have to be connected to the safety bus, for example, by means of electrical or optical cables which involves a degree of complexity in terms of cabling and increases the risk of cabling errors; however, a radio connection is also conceivable which involves the risk of configuration errors.
The association of the individual electrical safety circuits or the associated laser processing units thereof with the respective lasers is intended to be stored in a safety matrix of the safety PLC, which matrix is non-changeable and consequently secure in accordance with standard provisions. Via the safety PLC, it is consequently uniquely determined which laser is intended to be switched off or blocked in the event of an open safety circuit of a laser processing unit. Owing to the fixedly predetermined safety matrix, in the case of a plurality of lasers, a laser light cable must neither be switched from one laser to another laser nor must it be switched from a laser processing unit of one laser to a laser processing unit of another laser since, in the case of an open safety circuit, this does not then lead to the laser which is actually connected being switched off.